The dangling carrot of British and Irish Lions squad places provides the backdrop to this year's Six Nations championship in which England and France vie for favouritism and Wales seek to retain their title off the back of seven successive defeats.

At Wednesday's official tournament launch in London coaches and captains took turns to stress how form counts for little in the annual northern hemisphere set-to and Wales will certainly hope that is the case after a dismal and somewhat mystifying run that followed their third grand slam in eight years.

Now under the full-time care of Rob Howley as regular coach Warren Gatland concentrates on his Lions duties ahead of the tour of Australia, Wales kick off their defence at home to Ireland on February 2.

Their last-gasp Dublin victory in the opening game of last year's tournament propelled them towards the title and captain Sam Warburton knows they need to repeat that success at the Millennium Stadium to lift the gathering gloom.

"It is a really nice feeling going into the tournament as reigning champions. We can take great confidence from that," he said.

"We might not have done as well results-wise in the last six months, but particularly against Australia, a lot of those results have been by one or two points and could easily have gone our way.

"It is very hard to predict who is going to play well."

Ireland, who have lost their last three matches against Wales, including the 2011 World Cup quarter-final, managed only two victories last season and were also on a poor run before finishing their November series on a high by thrashing Argentina.

Brian O'Driscoll will drag his battered body through one more tournament, hoping to secure a Lions slot, but the Irish captaincy has passed to number eight Jamie Heaslip.

"I'm still buzzing about the whole thing," said Heaslip. "When Declan told me last week I had to stop myself climbing over the table and kissing him."

NO INVOLVEMENT

Watching that opening Cardiff match with his Lions cap on will be Gatland who will have no involvement with Welsh team matters.

"Having a Lions tour in the summer gives a different feel to the whole season," said Howley, a former player and assistant coach for the combined team.

"Right from pre-season players are working to be physically right for such a long season. In the Autumn they put themselves in the shop window and then again in the Six Nations when they are going against their potential rivals."

Until the last match of their Autumn series not many England players would have been checking out flight times to Sydney but everything changed in that memorable 38-21 victory over New Zealand.

The fixture list is marginally in their favour too, with France also coming to London in one of three home games, though away matches in Ireland and, on the final day, Wales, are hardly straightforward.

They start at home to Scotland on February 2 and though the points difference in their last four meetings averages just over four per match in England's favour Scotland have not won at Twickenham for 30 years.

"The driver for us now is to do what we did against New Zealand on a consistent basis," said coach Stuart Lancaster, who this time last year was approaching his first game as interim coach.

Scotland are also under new management with Australian Scott Johnson taking charge after Andy Robinson resigned following their home defeat by Tonga.

Forced to choose from a desperately shallow pool of talent, Johnson's team seem certain to be fighting it out with Italy to avoid last place, the matter likely to be decided on February 2 when the two meet at Murrayfield.

Italy coach Jacques Brunel has managed three wins in his 10 games since replacing Nick Mallett after the 2011 World Cup though they were agonisingly close to holding Australia to a draw in their last match in November.

The French were the most consistent of the European sides in November, thrashing Australia and also accounting for Argentina and Samoa, and will expect to improve on last year's disappointing fourth-placed finish.

However, while most of the rest of the tournament's leading players are already in their national camps preparing, the bulk of the French squad will be involved in league games on Thursday and Friday.

"We just cross our fingers that we won't have too many injuries," said coach Philippe Saint Andre.

"But the Six Nations is a fantastic event and it looks as if you run 100 metres but we start 10 metres behind (the other teams). So you need to run 110 metres.

"We know the big problem of French rugby is to be consistent. We've won four games consecutively, this is quite a big event for us, but we would like more and more of this."